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Montalbano A, Sala C, Altadonna GC, Becchetti A, Arcangeli A. High throughput clone screening on overexpressed hERG1 and Kv1.3 potassium channels using ion channel reader (ICR) label free technology. Heliyon 2023; 9:e20112. [PMID: 37767500 PMCID: PMC10520782 DOI: 10.1016/j.heliyon.2023.e20112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 08/27/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023] Open
Abstract
Pharmacological studies aimed at the development of newly synthesized drugs directed against ion channels (as well as genetic studies of ion channel mutations) involve the development and use of transfected cells. However, the identification of the best clone, in terms of transfection efficiency, is often a time consuming procedure when performed through traditional methods such as manual patch-clamp. On the other hand, the use of other faster techniques, such as for example the IF, are not informative on the effective biological functionality of the transfected ion channel(s). In the present work, we used the high throughput automated ion channel reader (ICR) technology (ICR8000 Aurora Biomed Inc.) that combine atomic absorption spectroscopy with a patented microsampling process to accurately measure ion flux in cell-based screening assays. This technology indeed helped us to evaluate the transfection efficiency of hERG1 and hKv1.3 channels respectively on the HEK-293 and CHO cellular models. Moreover, as proof of the validity of this innovative method, we have corroborated these data with the functional characterization of the potassium currents carried out by the same clones through patch-clamp recordings. The results obtained in our study are promising and represent a valid methodological strategy to screen a large number of clones simultaneously and to pharmacologically evaluate their functionality within an extremely faster timeframe.
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Affiliation(s)
- Alberto Montalbano
- Department of Experimental and Clinical Medicine, University of Florence, I-50134, Florence, Italy
| | - Cesare Sala
- Department of Experimental and Clinical Medicine, University of Florence, I-50134, Florence, Italy
| | | | - Andrea Becchetti
- University of Milano-Bicocca, Department of Biotechnology and Biosciences, Piazza della Scienza 2, I-20126, Milano, Italy
| | - Annarosa Arcangeli
- Department of Experimental and Clinical Medicine, University of Florence, I-50134, Florence, Italy
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2
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Physicochemical QSAR analysis of hERG inhibition revisited: towards a quantitative potency prediction. J Comput Aided Mol Des 2022; 36:837-849. [PMID: 36305984 DOI: 10.1007/s10822-022-00483-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/04/2022] [Indexed: 01/07/2023]
Abstract
In an earlier study (Didziapetris R & Lanevskij K (2016). J Comput Aided Mol Des. 30:1175-1188) we collected a database of publicly available hERG inhibition data for almost 6700 drug-like molecules and built a probabilistic Gradient Boosting classifier with a minimal set of physicochemical descriptors (log P, pKa, molecular size and topology parameters). This approach favored interpretability over statistical performance but still achieved an overall classification accuracy of 75%. In the current follow-up work we expanded the database (provided in Supplementary Information) to almost 9400 molecules and performed temporal validation of the model on a set of novel chemicals from recently published lead optimization projects. Validation results showed almost no performance degradation compared to the original study. Additionally, we rebuilt the model using AFT (Accelerated Failure Time) learning objective in XGBoost, which accepts both quantitative and censored data often reported in protein inhibition studies. The new model achieved a similar level of accuracy of discerning hERG blockers from non-blockers at 10 µM threshold, which can be conceived as close to the performance ceiling for methods aiming to describe only non-specific ligand interactions with hERG. Yet, this model outputs quantitative potency values (IC50) and is not tied to a particular classification cut-off. pIC50 from patch-clamp measurements can be predicted with R2 ≈ 0.4 and MAE < 0.5, which enables ligand ranking according to their expected potency levels. The employed approach can be valuable for quantitative modeling of various ADME and drug safety endpoints with a high prevalence of censored data.
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3
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Cortopassi WA, Gunderson E, Annunciato Y, Silva A, dos Santos Ferreira A, Garcia Teles CB, Pimentel AS, Ramamoorthi R, Gazarini ML, Meneghetti MR, Guido R, Pereira DB, Jacobson MP, Krettli AU, Caroline C Aguiar A. Fighting Plasmodium chloroquine resistance with acetylenic chloroquine analogues. Int J Parasitol Drugs Drug Resist 2022; 20:121-128. [PMID: 36375339 PMCID: PMC9771834 DOI: 10.1016/j.ijpddr.2022.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 10/17/2022] [Accepted: 10/18/2022] [Indexed: 11/07/2022]
Abstract
Malaria is among the tropical diseases that cause the most deaths in Africa. Around 500,000 malaria deaths are reported yearly among African children under the age of five. Chloroquine (CQ) is a low-cost antimalarial used worldwide for the treatment of Plasmodium vivax malaria. Due to resistance mechanisms, CQ is no longer effective against most malaria cases caused by P. falciparum. The World Health Organization recommends artemisinin combination therapies for P. falciparum malaria, but resistance is emerging in Southeast Asia and some parts of Africa. Therefore, new medicines for treating malaria are urgently needed. Previously, our group identified the 4-aminoquinoline DAQ, a CQ analog containing an acetylenic bond in its side chain, which overcomes CQ resistance in K1 P. falciparum strains. In this work, the antiplasmodial profile, drug-like properties, and pharmacokinetics of DAQ were further investigated. DAQ showed no cross-resistance against standard CQ-resistant strains (e.g., Dd2, IPC 4912, RF12) nor against P. falciparum and P. vivax isolates from patients in the Brazilian Amazon. Using drug pressure assays, DAQ showed a low propensity to generate resistance. DAQ showed considerable solubility but low metabolic stability. The main metabolite was identified as a mono N-deethylated derivative (DAQM), which also showed significant inhibitory activity against CQ-resistant P. falciparum strains. Our findings indicated that the presence of a triple bond in CQ-analogues may represent a low-cost opportunity to overcome known mechanisms of resistance in the malaria parasite.
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Affiliation(s)
- Wilian A. Cortopassi
- Department of Pharmaceutical Chemistry, University of California, San Francisco, USA
| | - Emma Gunderson
- Department of Pharmaceutical Chemistry, University of California, San Francisco, USA
| | - Yasmin Annunciato
- Department of Biosciences, Federal University of São Paulo, Santos, SP, Brazil
| | - Antony.E.S. Silva
- Group of Catalysis and Chemical Reactivity Group, Institute of Chemistry and Biotechnology, Federal University of Alagoas, Maceió, AL, Brazil
| | | | | | - Andre S. Pimentel
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro, RJ, Brazil
| | | | - Marcos L Gazarini
- Department of Biosciences, Federal University of São Paulo, Santos, SP, Brazil
| | - Mario R. Meneghetti
- Group of Catalysis and Chemical Reactivity Group, Institute of Chemistry and Biotechnology, Federal University of Alagoas, Maceió, AL, Brazil
| | - Rafael.V.C. Guido
- São Carlos Institute of Physics, University of Sao Paulo, Av. João Dagnone, 1100 - Santa Angelina, São Carlos, SP, 13563-120, Brazil
| | - Dhelio B. Pereira
- Research Center in Tropical Medicine of Rondônia, Porto Velho, Rondônia, Brazil
| | - Matthew P. Jacobson
- Department of Pharmaceutical Chemistry, University of California, San Francisco, USA
| | - Antoniana U. Krettli
- Malaria Laboratory, René Rachou Research Center, FIOCRUZ, Belo Horizonte, MG, Brazil,Corresponding author.
| | - Anna Caroline C Aguiar
- Department of Biosciences, Federal University of São Paulo, Santos, SP, Brazil,São Carlos Institute of Physics, University of Sao Paulo, Av. João Dagnone, 1100 - Santa Angelina, São Carlos, SP, 13563-120, Brazil,Corresponding author.Department of Biosciences, Federal University of São Paulo, Santos, SP, Brazil.
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4
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Fallah HP, Ahuja E, Lin H, Qi J, He Q, Gao S, An H, Zhang J, Xie Y, Liang D. A Review on the Role of TRP Channels and Their Potential as Drug Targets_An Insight Into the TRP Channel Drug Discovery Methodologies. Front Pharmacol 2022; 13:914499. [PMID: 35685622 PMCID: PMC9170958 DOI: 10.3389/fphar.2022.914499] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 04/27/2022] [Indexed: 01/13/2023] Open
Abstract
Transient receptor potential (TRP) proteins are a large group of ion channels that control many physiological functions in our body. These channels are considered potential therapeutic drug targets for various diseases such as neurological disorders, cancers, cardiovascular disease, and many more. The Nobel Prize in Physiology/Medicine in the year 2021 was awarded to two scientists for the discovery of TRP and PIEZO ion channels. Improving our knowledge of technologies for their study is essential. In the present study, we reviewed the role of TRP channel types in the control of normal physiological functions as well as disease conditions. Also, we discussed the current and novel technologies that can be used to study these channels successfully. As such, Flux assays for detecting ionic flux through ion channels are among the core and widely used tools for screening drug compounds. Technologies based on these assays are available in fully automated high throughput set-ups and help detect changes in radiolabeled or non-radiolabeled ionic flux. Aurora's Ion Channel Reader (ICR), which works based on label-free technology of flux assay, offers sensitive, accurate, and reproducible measurements to perform drug ranking matching with patch-clamp (gold standard) data. The non-radiolabeled trace-based flux assay coupled with the ICR detects changes in various ion types, including potassium, calcium, sodium, and chloride channels, by using appropriate tracer ions. This technology is now considered one of the very successful approaches for analyzing ion channel activity in modern drug discovery. It could be a successful approach for studying various ion channels and transporters, including the different members of the TRP family of ion channels.
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Affiliation(s)
| | - Ekta Ahuja
- Aurora Biomed Inc., Vancouver, BC, Canada
| | | | - Jinlong Qi
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, China
| | - Qian He
- Aurora Discovery Inc., Foshan, China
| | - Shan Gao
- Aurora Discovery Inc., Foshan, China
| | | | | | | | - Dong Liang
- Aurora Biomed Inc., Vancouver, BC, Canada
- Aurora Discovery Inc., Foshan, China
- Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
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5
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Bell DC, Fermini B. Use of automated patch clamp in cardiac safety assessment: Past, present & future perspectives. J Pharmacol Toxicol Methods 2021; 111:107114. [PMID: 34400309 DOI: 10.1016/j.vascn.2021.107114] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
There is no doubt that automated patch clamp (APC) technology has revolutionized research in biomedical science. High throughput ion channel screening is now an integral part of the development and safety profiling of the majority of new chemical entities currently developed to address unmet medical needs. The increased throughput it provides has significantly improved the ability to overcome the time-consuming, low throughput bottlenecks resulting from the more conventional manual patch clamp method, considered the 'gold standard', for studying ion channel function and pharmacology. While systems offering the luxury of automation have only been commercially available for two decades, the road leading to this new technology is long and rich in seminal, hands-on, studies dating back as far as the 18th century. So where does this technology currently stand, and what will it look like in the future? In the current article, we review the scientific history leading to the development of APC systems, examine key drivers in the rapid development of this technology (such as failed ion channel programmes and the issue of drug-induced hERG inhibition and QT interval prolongation), highlight key capabilities and finally provide some perspective on the current and future impact of the technology on cardiac safety assessment and biomedical science.
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Affiliation(s)
- Damian C Bell
- Sophion Bioscience A/S, Ballerup, Copenhagen, Denmark.
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6
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Bell DC, Fermini B. Use of automated patch clamp in cardiac safety assessment: past, present and future perspectives. J Pharmacol Toxicol Methods 2021; 110:107072. [PMID: 33962018 DOI: 10.1016/j.vascn.2021.107072] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 04/23/2021] [Accepted: 05/02/2021] [Indexed: 12/14/2022]
Abstract
There is no doubt that automated patch clamp (APC) technology has revolutionized research in biomedical science. High throughput ion channel screening is now an integral part of the development and safety profiling of the majority of new chemical entities currently developed to address unmet medical needs. The increased throughput it provides has significantly improved the ability to overcome the time-consuming, low throughput bottlenecks resulting from the more conventional manual patch clamp method, considered the 'gold standard', for studying ion channel function and pharmacology. While systems offering the luxury of automation have only been commercially available for two decades, the road leading to this new technology is long and rich in seminal, hands-on, studies dating back as far as the 18th century. So where does this technology currently stand, and what will it look like in the future? In the current article, we review the scientific history leading to the development of APC systems, examine key drivers in the rapid development of this technology (such as failed ion channel programmes and the issue of drug-induced hERG inhibition and QT interval prolongation), highlight key capabilities and finally provide some perspective on the current and future impact of the technology on cardiac safety assessment and biomedical science.
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7
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Bell DC, Dallas ML. Advancing Ion Channel Research with Automated Patch Clamp (APC) Electrophysiology Platforms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1349:21-32. [DOI: 10.1007/978-981-16-4254-8_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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8
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Yang PC, DeMarco KR, Aghasafari P, Jeng MT, Dawson JRD, Bekker S, Noskov SY, Yarov-Yarovoy V, Vorobyov I, Clancy CE. A Computational Pipeline to Predict Cardiotoxicity: From the Atom to the Rhythm. Circ Res 2020; 126:947-964. [PMID: 32091972 DOI: 10.1161/circresaha.119.316404] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
RATIONALE Drug-induced proarrhythmia is so tightly associated with prolongation of the QT interval that QT prolongation is an accepted surrogate marker for arrhythmia. But QT interval is too sensitive a marker and not selective, resulting in many useful drugs eliminated in drug discovery. OBJECTIVE To predict the impact of a drug from the drug chemistry on the cardiac rhythm. METHODS AND RESULTS In a new linkage, we connected atomistic scale information to protein, cell, and tissue scales by predicting drug-binding affinities and rates from simulation of ion channel and drug structure interactions and then used these values to model drug effects on the hERG channel. Model components were integrated into predictive models at the cell and tissue scales to expose fundamental arrhythmia vulnerability mechanisms and complex interactions underlying emergent behaviors. Human clinical data were used for model framework validation and showed excellent agreement, demonstrating feasibility of a new approach for cardiotoxicity prediction. CONCLUSIONS We present a multiscale model framework to predict electrotoxicity in the heart from the atom to the rhythm. Novel mechanistic insights emerged at all scales of the system, from the specific nature of proarrhythmic drug interaction with the hERG channel, to the fundamental cellular and tissue-level arrhythmia mechanisms. Applications of machine learning indicate necessary and sufficient parameters that predict arrhythmia vulnerability. We expect that the model framework may be expanded to make an impact in drug discovery, drug safety screening for a variety of compounds and targets, and in a variety of regulatory processes.
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Affiliation(s)
- Pei-Chi Yang
- From the Department of Physiology and Membrane Biology (P.-C.Y., K.R.D., P.A., M.-T.J., J.R.D.D., V.Y.-Y., I.V., C.E.C.), University of California Davis
| | - Kevin R DeMarco
- From the Department of Physiology and Membrane Biology (P.-C.Y., K.R.D., P.A., M.-T.J., J.R.D.D., V.Y.-Y., I.V., C.E.C.), University of California Davis
| | - Parya Aghasafari
- From the Department of Physiology and Membrane Biology (P.-C.Y., K.R.D., P.A., M.-T.J., J.R.D.D., V.Y.-Y., I.V., C.E.C.), University of California Davis
| | - Mao-Tsuen Jeng
- From the Department of Physiology and Membrane Biology (P.-C.Y., K.R.D., P.A., M.-T.J., J.R.D.D., V.Y.-Y., I.V., C.E.C.), University of California Davis
| | - John R D Dawson
- From the Department of Physiology and Membrane Biology (P.-C.Y., K.R.D., P.A., M.-T.J., J.R.D.D., V.Y.-Y., I.V., C.E.C.), University of California Davis.,Biophysics Graduate Group (J.R.D.D.), University of California Davis
| | - Slava Bekker
- Department of Science and Engineering, American River College, Sacramento, CA (S.B.)
| | - Sergei Y Noskov
- Faculty of Science, Centre for Molecular Simulations and Department of Biological Sciences, University of Calgary, Alberta, Canada (S.Y.N.)
| | - Vladimir Yarov-Yarovoy
- From the Department of Physiology and Membrane Biology (P.-C.Y., K.R.D., P.A., M.-T.J., J.R.D.D., V.Y.-Y., I.V., C.E.C.), University of California Davis
| | - Igor Vorobyov
- From the Department of Physiology and Membrane Biology (P.-C.Y., K.R.D., P.A., M.-T.J., J.R.D.D., V.Y.-Y., I.V., C.E.C.), University of California Davis.,Department of Pharmacology (I.V., C.E.C.), University of California Davis
| | - Colleen E Clancy
- From the Department of Physiology and Membrane Biology (P.-C.Y., K.R.D., P.A., M.-T.J., J.R.D.D., V.Y.-Y., I.V., C.E.C.), University of California Davis.,Department of Pharmacology (I.V., C.E.C.), University of California Davis
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9
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Shi C, Wang Q, Liao X, Ge H, Huo G, Zhang L, Chen N, Zhai X, Hong Y, Wang L, Han Y, Xiao W, Wang Z, Shi W, Mao Y, Yu J, Xia G, Liu Y. Discovery of 6-(2-(dimethylamino)ethyl)-N-(5-fluoro-4-(4-fluoro-1-isopropyl-2-methyl-1H-benzo[d]imidazole-6-yl)pyrimidin-2-yl)-5,6,7,8-tetrahydro-1,6-naphthyridin-2-amine as a highly potent cyclin-dependent kinase 4/6 inhibitor for treatment of cancer. Eur J Med Chem 2019; 178:352-364. [PMID: 31200237 DOI: 10.1016/j.ejmech.2019.06.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 06/03/2019] [Accepted: 06/03/2019] [Indexed: 12/09/2022]
Abstract
Targeting CDK4/6 has been identified as an effective therapeutics for treatment of cancer. We herein reported the discovery of a series of 6-(2-(methylamino)ethyl)-5,6,7,8-tetrahydro-1,6-naphthyridin-2-amine derivatives as CDK4/6 inhibitors against cancer. Compound 3c, which displayed high potency and selectivity on CDK4/6 (IC50 = 0.710/1.10 nM) over a variety of other kinases, possessed desirable antiproliferative activities, excellent metabolic properties, and favorable pharmacokinetic characters. In MCF-7, Colo-205, and A549 xenograft models, compound 3c exhibited significant tumor growth inhibitions with low toxicities, which could be a promising drug candidate for further development.
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Affiliation(s)
- Chen Shi
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Qian Wang
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Xuemei Liao
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Hui Ge
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Guoyong Huo
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Leduo Zhang
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Na Chen
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Xiong Zhai
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Yuan Hong
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Li Wang
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Yanan Han
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Wenbo Xiao
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Zhe Wang
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Weijun Shi
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Yu Mao
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Jianxin Yu
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China
| | - Guangxin Xia
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China.
| | - Yanjun Liu
- Central Research Institute, Shanghai Pharmaceuticals Holding Co., Ltd., Building 5, No. 898 Halei Road, Zhangjiang Hi-tech Park, Pudong New Area, Shanghai, 201203, PR China.
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10
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Dockendorff C, Gandhi DM, Kimball IH, Eum KS, Rusinova R, Ingólfsson HI, Kapoor R, Peyear T, Dodge MW, Martin SF, Aldrich RW, Andersen OS, Sack JT. Synthetic Analogues of the Snail Toxin 6-Bromo-2-mercaptotryptamine Dimer (BrMT) Reveal That Lipid Bilayer Perturbation Does Not Underlie Its Modulation of Voltage-Gated Potassium Channels. Biochemistry 2018; 57:2733-2743. [PMID: 29616558 PMCID: PMC6007853 DOI: 10.1021/acs.biochem.8b00292] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Drugs do not act solely by canonical ligand-receptor binding interactions. Amphiphilic drugs partition into membranes, thereby perturbing bulk lipid bilayer properties and possibly altering the function of membrane proteins. Distinguishing membrane perturbation from more direct protein-ligand interactions is an ongoing challenge in chemical biology. Herein, we present one strategy for doing so, using dimeric 6-bromo-2-mercaptotryptamine (BrMT) and synthetic analogues. BrMT is a chemically unstable marine snail toxin that has unique effects on voltage-gated K+ channel proteins, making it an attractive medicinal chemistry lead. BrMT is amphiphilic and perturbs lipid bilayers, raising the question of whether its action against K+ channels is merely a manifestation of membrane perturbation. To determine whether medicinal chemistry approaches to improve BrMT might be viable, we synthesized BrMT and 11 analogues and determined their activities in parallel assays measuring K+ channel activity and lipid bilayer properties. Structure-activity relationships were determined for modulation of the Kv1.4 channel, bilayer partitioning, and bilayer perturbation. Neither membrane partitioning nor bilayer perturbation correlates with K+ channel modulation. We conclude that BrMT's membrane interactions are not critical for its inhibition of Kv1.4 activation. Further, we found that alkyl or ether linkages can replace the chemically labile disulfide bond in the BrMT pharmacophore, and we identified additional regions of the scaffold that are amenable to chemical modification. Our work demonstrates a strategy for determining if drugs act by specific interactions or bilayer-dependent mechanisms, and chemically stable modulators of Kv1 channels are reported.
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Affiliation(s)
- Chris Dockendorff
- Department of Chemistry , Marquette University , P.O. Box 1881, Milwaukee , Wisconsin 53201-1881 , United States
| | - Disha M Gandhi
- Department of Chemistry , Marquette University , P.O. Box 1881, Milwaukee , Wisconsin 53201-1881 , United States
| | - Ian H Kimball
- Department of Physiology & Membrane Biology , University of California , 1 Shields Avenue , Davis , California 95616 , United States
| | - Kenneth S Eum
- Department of Physiology & Membrane Biology , University of California , 1 Shields Avenue , Davis , California 95616 , United States
| | - Radda Rusinova
- Department of Physiology and Biophysics , Weill Cornell Medical College , New York , New York 10065 , United States
| | - Helgi I Ingólfsson
- Department of Physiology and Biophysics , Weill Cornell Medical College , New York , New York 10065 , United States
| | - Ruchi Kapoor
- Department of Physiology and Biophysics , Weill Cornell Medical College , New York , New York 10065 , United States
| | - Thasin Peyear
- Department of Physiology and Biophysics , Weill Cornell Medical College , New York , New York 10065 , United States
| | - Matthew W Dodge
- Department of Chemistry , Marquette University , P.O. Box 1881, Milwaukee , Wisconsin 53201-1881 , United States
| | - Stephen F Martin
- Department of Chemistry , University of Texas at Austin , 1 University Station , Austin , Texas 78712 , United States
| | - Richard W Aldrich
- Department of Neuroscience , University of Texas at Austin , 1 University Station , Austin , Texas 78712 , United States
| | - Olaf S Andersen
- Department of Physiology and Biophysics , Weill Cornell Medical College , New York , New York 10065 , United States
| | - Jon T Sack
- Department of Physiology & Membrane Biology , University of California , 1 Shields Avenue , Davis , California 95616 , United States
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11
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Gill S, Gill R, Wen Y, Enderle T, Roth D, Liang D. A High-Throughput Screening Assay for NKCC1 Cotransporter Using Nonradioactive Rubidium Flux Technology. Assay Drug Dev Technol 2018. [PMID: 28631939 DOI: 10.1089/adt.2017.787] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A high-throughput screening (HTS) assay was developed for cotransporter, NKCC1, which is a potential target for the treatment of diverse disorders. This nonradioactive rubidium flux assay coupled with ion channel reader series provides a working screen for this target expressed in human embryonic kidney (HEK) cell line. An eightfold window of detection was achieved with the optimized assay. This new functional assay offered a robust working model for NKCC1 in determining reliable and concordant rank orders of the test compounds supporting its sensitivity and specificity. The robustness of manual assay indicated by Z' of 0.9 qualified its amenability to automation. The Z' of 0.7 was displayed by automated assay employed in high-throughput screening of compound libraries against this target. Being electrically neutral, the NKCC1 screening is difficult to achieve by both manual and automated electrophysiological techniques. These techniques, although considered gold standard, suffer from their inherent problems of being too slow to be in high-throughput format and with high running costs. In addition to being a functional assay for NKCC1, it is nontoxic as compared with thallium flux assay, which is prone to generate high number of false-positive/false-negative rates because of its innate fluorescence issues.
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Affiliation(s)
| | | | - Yang Wen
- 2 Roche Innovation Center Basel , Hoffmann-La Roche, Basel, Switzerland
| | - Thilo Enderle
- 2 Roche Innovation Center Basel , Hoffmann-La Roche, Basel, Switzerland
| | - Doris Roth
- 2 Roche Innovation Center Basel , Hoffmann-La Roche, Basel, Switzerland
| | - Dong Liang
- 1 Aurora Biomed Inc. , Vancouver, Canada
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12
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Streit J, Kleinlogel S. Dynamic all-optical drug screening on cardiac voltage-gated ion channels. Sci Rep 2018; 8:1153. [PMID: 29348631 PMCID: PMC5773578 DOI: 10.1038/s41598-018-19412-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 12/27/2017] [Indexed: 11/09/2022] Open
Abstract
Voltage-gated ion channels (VGCs) are prime targets for the pharmaceutical industry, but drug profiling on VGCs is challenging, since drug interactions are confined to specific conformational channel states mediated by changes in transmembrane potential. Here we combined various optogenetic tools to develop dynamic, high-throughput drug profiling assays with defined light-step protocols to interrogate VGC states on a millisecond timescale. We show that such light-induced electrophysiology (LiEp) yields high-quality pharmacological data with exceptional screening windows for drugs acting on the major cardiac VGCs, including hNav1.5, hKv1.5 and hERG. LiEp-based screening remained robust when using a variety of optogenetic actuators (ChR2, ChR2(H134R), CatCh, ChR2-EYFP-βArchT) and different types of organic (RH421, Di-4-ANBDQPQ, BeRST1) or genetic voltage sensors (QuasAr1). The tractability of LiEp allows a versatile and precise alternative to state-of-the-art VGC drug screening platforms such as automated electrophysiology or FLIPR readers.
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Affiliation(s)
- Jonas Streit
- Institute of Physiology, University of Bern, Bühlplatz 5, 3012, Bern, Switzerland
| | - Sonja Kleinlogel
- Institute of Physiology, University of Bern, Bühlplatz 5, 3012, Bern, Switzerland.
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13
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Wu D, Zhang T, Chen Y, Huang Y, Geng H, Yu Y, Zhang C, Lai Z, Wu Y, Guo X, Chen J, Luo HB. Discovery and Optimization of Chromeno[2,3-c]pyrrol-9(2H)-ones as Novel Selective and Orally Bioavailable Phosphodiesterase 5 Inhibitors for the Treatment of Pulmonary Arterial Hypertension. J Med Chem 2017; 60:6622-6637. [DOI: 10.1021/acs.jmedchem.7b00523] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Deyan Wu
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Tianhua Zhang
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Yiping Chen
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Yadan Huang
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Haiju Geng
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Yanfa Yu
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Chen Zhang
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Zengwei Lai
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Yinuo Wu
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Xiaolei Guo
- Infinitus (China) Co. Ltd., Guangzhou 510663, China
| | - Jianwen Chen
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
| | - Hai-Bin Luo
- School
of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, P. R. China
- Collaborative
Innovation Center of High Performance Computing, National University of Defense Technology, Changsha 410073, China
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14
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Bell DC, Dallas ML. Using automated patch clamp electrophysiology platforms in pain-related ion channel research: insights from industry and academia. Br J Pharmacol 2017. [PMID: 28622411 DOI: 10.1111/bph.13916] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Automated patch clamp (APC) technology was first developed at the turn of the millennium. The increased throughput it afforded promised a new paradigm in ion channel recordings, offering the potential to overcome the time-consuming, low-throughput bottleneck, arising from manual patch clamp investigations. This has relevance to the fast-paced development of novel therapies for chronic pain. This review highlights the advances in technology, using select examples that have facilitated APC usage in both industry and academia. It covers both first generation and the latest developments in second-generation platforms. In addition, it also provides an overview of the pain research field and how APC platforms have furthered our understanding of ion channel research and the development of pharmacological tools and therapeutics. APC platforms have much to offer to the ion channel research community, and this review highlights areas of best practice for both academia and industry. The impact of APC platforms and the prospects of ion channel research and improved therapeutics for chronic pain will be evaluated. LINKED ARTICLES This article is part of a themed section on Recent Advances in Targeting Ion Channels to Treat Chronic Pain. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.12/issuetoc.
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Affiliation(s)
| | - Mark L Dallas
- School of Pharmacy, University of Reading, Reading, UK
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15
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Tadesse S, Yu M, Mekonnen LB, Lam F, Islam S, Tomusange K, Rahaman MH, Noll B, Basnet SKC, Teo T, Albrecht H, Milne R, Wang S. Highly Potent, Selective, and Orally Bioavailable 4-Thiazol-N-(pyridin-2-yl)pyrimidin-2-amine Cyclin-Dependent Kinases 4 and 6 Inhibitors as Anticancer Drug Candidates: Design, Synthesis, and Evaluation. J Med Chem 2017; 60:1892-1915. [PMID: 28156111 DOI: 10.1021/acs.jmedchem.6b01670] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Cyclin D dependent kinases (CDK4 and CDK6) regulate entry into S phase of the cell cycle and are validated targets for anticancer drug discovery. Herein we detail the discovery of a novel series of 4-thiazol-N-(pyridin-2-yl)pyrimidin-2-amine derivatives as highly potent and selective inhibitors of CDK4 and CDK6. Medicinal chemistry optimization resulted in 83, an orally bioavailable inhibitor molecule with remarkable selectivity. Repeated oral administration of 83 caused marked inhibition of tumor growth in MV4-11 acute myeloid leukemia mouse xenografts without having a negative effect on body weight and showing any sign of clinical toxicity. The data merit 83 as a clinical development candidate.
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Affiliation(s)
- Solomon Tadesse
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Mingfeng Yu
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Laychiluh B Mekonnen
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Frankie Lam
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Saiful Islam
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Khamis Tomusange
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Muhammed H Rahaman
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Benjamin Noll
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Sunita K C Basnet
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Theodosia Teo
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Hugo Albrecht
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Robert Milne
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
| | - Shudong Wang
- Center for Drug Discovery and Development, Sansom Institute for Health Research, School of Pharmacy and Medical Sciences, and Center for Cancer Biology, University of South Australia , Adelaide, South Australia 5001, Australia
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16
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Didziapetris R, Lanevskij K. Compilation and physicochemical classification analysis of a diverse hERG inhibition database. J Comput Aided Mol Des 2016; 30:1175-1188. [DOI: 10.1007/s10822-016-9986-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 10/21/2016] [Indexed: 10/20/2022]
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17
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Picones A, Loza-Huerta A, Segura-Chama P, Lara-Figueroa CO. Contribution of Automated Technologies to Ion Channel Drug Discovery. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2016; 104:357-378. [DOI: 10.1016/bs.apcsb.2016.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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18
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Yarov-Yarovoy V, Allen TW, Clancy CE. Computational Models for Predictive Cardiac Ion Channel Pharmacology. ACTA ACUST UNITED AC 2014; 14:3-10. [PMID: 26635886 DOI: 10.1016/j.ddmod.2014.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A wealth of experimental data exists describing the elementary building blocks of complex physiological systems. However, it is increasingly apparent in the biomedical sciences that mechanisms of biological function cannot be observed or readily predicted via study of constituent elements alone. This is especially clear in the longstanding failures in prediction of effects of drug treatment for heart rhythm disturbances. These failures stem in part from classical assumptions that have been made in cardiac antiarrhythmic drug development - that a drug operates by one mechanism via one target receptor that arises from one gene.
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Affiliation(s)
| | - Toby W Allen
- Department of Chemistry, University of California, Davis
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19
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Palomino-Morales R, Alejandre MJ, Perales S, Torres C, Linares A. Effect of PUFAs on extracellular matrix production and remodeling in vascular smooth muscle cell cultures in an atherosclerotic model. EUR J LIPID SCI TECH 2014. [DOI: 10.1002/ejlt.201400141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Rogelio Palomino-Morales
- Faculty of Sciences, Department of Biochemistry and Molecular Biology I; Campus Universitario de Fuentenueva, University of Granada; Granada Spain
| | - M. Jose Alejandre
- Faculty of Sciences, Department of Biochemistry and Molecular Biology I; Campus Universitario de Fuentenueva, University of Granada; Granada Spain
| | - Sonia Perales
- Faculty of Sciences, Department of Biochemistry and Molecular Biology I; Campus Universitario de Fuentenueva, University of Granada; Granada Spain
| | - Carolina Torres
- Faculty of Sciences, Department of Biochemistry and Molecular Biology I; Campus Universitario de Fuentenueva, University of Granada; Granada Spain
| | - Ana Linares
- Faculty of Sciences, Department of Biochemistry and Molecular Biology I; Campus Universitario de Fuentenueva, University of Granada; Granada Spain
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20
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Babcock JJ, Du F, Xu K, Wheelan SJ, Li M. Integrated analysis of drug-induced gene expression profiles predicts novel hERG inhibitors. PLoS One 2013; 8:e69513. [PMID: 23936032 PMCID: PMC3720659 DOI: 10.1371/journal.pone.0069513] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 06/07/2013] [Indexed: 11/19/2022] Open
Abstract
Growing evidence suggests that drugs interact with diverse molecular targets mediating both therapeutic and toxic effects. Prediction of these complex interactions from chemical structures alone remains challenging, as compounds with different structures may possess similar toxicity profiles. In contrast, predictions based on systems-level measurements of drug effect may reveal pharmacologic similarities not evident from structure or known therapeutic indications. Here we utilized drug-induced transcriptional responses in the Connectivity Map (CMap) to discover such similarities among diverse antagonists of the human ether-à-go-go related (hERG) potassium channel, a common target of promiscuous inhibition by small molecules. Analysis of transcriptional profiles generated in three independent cell lines revealed clusters enriched for hERG inhibitors annotated using a database of experimental measurements (hERGcentral) and clinical indications. As a validation, we experimentally identified novel hERG inhibitors among the unannotated drugs in these enriched clusters, suggesting transcriptional responses may serve as predictive surrogates of cardiotoxicity complementing existing functional assays.
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Affiliation(s)
- Joseph J. Babcock
- The Solomon H. Snyder Department of Neuroscience and High Throughput Biology Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Fang Du
- The Solomon H. Snyder Department of Neuroscience and High Throughput Biology Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Kaiping Xu
- Johns Hopkins Ion Channel Center (JHICC), The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Sarah J. Wheelan
- Department of Oncology, Division of Biostatistics and Bioinformatics, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail: (ML); (SJW)
| | - Min Li
- The Solomon H. Snyder Department of Neuroscience and High Throughput Biology Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Johns Hopkins Ion Channel Center (JHICC), The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail: (ML); (SJW)
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21
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Larsen EKU, Larsen NB. One-step polymer surface modification for minimizing drug, protein, and DNA adsorption in microanalytical systems. LAB ON A CHIP 2013; 13:669-75. [PMID: 23254780 DOI: 10.1039/c2lc40750g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The non-specific adsorption of dissolved analytes strongly reduces the sensitivity and reliability in polymer microanalytical systems. Here, a one-step aqueous phase procedure modifies polymer material surfaces to strongly reduce their non-specific adsorption of a broad range of organic analytes including hydrophobic and hydrophilic drugs (0.23 < ClogP < 8.95), small and large proteins (insulin, albumin, IgG), and DNA. The coating is shown to limit the adsorption of even highly hydrophobic drugs (ClogP > 8) in their pharmaceutically relevant concentration range ≤100 nM. The low adsorption is mediated by photochemical conjugation, where polyethylene glycol (PEG) polymers in aqueous solution are covalently bound to the surface by UV illumination of dissolved benzophenone and a functionalized PEG. The method can coat the interior of polymer systems made from a range of materials commonly used in microanalytical systems, including polystyrene (PS), cyclic olefin copolymer (COC), liquid crystalline polymer (LCP), and polyimide (PI).
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Affiliation(s)
- Esben Kjær Unmack Larsen
- Department of Micro- and Nanotechnology, DTU Nanotech, Technical University of Denmark, Ørsteds Plads 345E, DK-2800 Kgs. Lyngby, Denmark
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22
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Yajuan X, Xin L, Zhiyuan L. A comparison of the performance and application differences between manual and automated patch-clamp techniques. CURRENT CHEMICAL GENOMICS 2012; 6:87-92. [PMID: 23346269 PMCID: PMC3549544 DOI: 10.2174/1875397301206010087] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 06/29/2012] [Accepted: 11/05/2012] [Indexed: 11/22/2022]
Abstract
The patch clamp technique is commonly used in electrophysiological experiments and offers direct insight into ion channel properties through the characterization of ion channel activity. This technique can be used to elucidate the interaction between a drug and a specific ion channel at different conformational states to understand the ion channel modulators' mechanisms. The patch clamp technique is regarded as a gold standard for ion channel research; however, it suffers from low throughput and high personnel costs. In the last decade, the development of several automated electrophysiology platforms has greatly increased the screen throughput of whole cell electrophysiological recordings. New advancements in the automated patch clamp systems have aimed to provide high data quality, high content, and high throughput. However, due to the limitations noted above, automated patch clamp systems are not capable of replacing manual patch clamp systems in ion channel research. While automated patch clamp systems are useful for screening large amounts of compounds in cell lines that stably express high levels of ion channels, the manual patch clamp technique is still necessary for studying ion channel properties in some research areas and for specific cell types, including primary cells that have mixed cell types and differentiated cells that derive from induced pluripotent stem cells (iPSCs) or embryonic stem cells (ESCs). Therefore, further improvements in flexibility with regard to cell types and data quality will broaden the applications of the automated patch clamp systems in both academia and industry.
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Affiliation(s)
- Xiao Yajuan
- Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
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23
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Davies MR, Mistry HB, Hussein L, Pollard CE, Valentin JP, Swinton J, Abi-Gerges N. An in silico canine cardiac midmyocardial action potential duration model as a tool for early drug safety assessment. Am J Physiol Heart Circ Physiol 2012; 302:H1466-80. [DOI: 10.1152/ajpheart.00808.2011] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cell lines expressing ion channels (IC) and the advent of plate-based electrophysiology device have enabled a molecular understanding of the action potential (AP) as a means of early QT assessment. We sought to develop an in silico AP (isAP) model that provides an assessment of the effect of a compound on the myocyte AP duration (APD) using concentration-effect curve data from a panel of five ICs (hNav1.5, hCav1.2, hKv4.3/hKChIP2.2, hKv7.1/hminK, hKv11.1). A test set of 53 compounds was selected to cover a range of selective and mixed IC modulators that were tested for their effects on optically measured APD. A threshold of >10% change in APD at 90% repolarization (APD90) was used to signify an effect at the top test concentration. To capture the variations observed in left ventricular midmyocardial myocyte APD data from 19 different dogs, the isAP model was calibrated to produce an ensemble of 19 model variants that could capture the shape and form of the APs and also quantitatively replicate dofetilide- and diltiazem-induced APD90 changes. Provided with IC panel data only, the isAP model was then used, blinded, to predict APD90 changes greater than 10%. At a simulated concentration of 30 μM and based on a criterion that six of the variants had to agree, isAP prediction was scored as showing greater than 80% predictivity of compound activity. Thus, early in drug discovery, the isAP model allows integrating separate IC data and is amenable to the throughput required for use as a virtual screen.
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Affiliation(s)
| | | | - L. Hussein
- Safety Pharmacology, Safety Assessment United Kingdom, AstraZeneca R&D, Macclesfield, United Kingdom
| | - C. E. Pollard
- Safety Pharmacology, Safety Assessment United Kingdom, AstraZeneca R&D, Macclesfield, United Kingdom
| | - J.-P. Valentin
- Safety Pharmacology, Safety Assessment United Kingdom, AstraZeneca R&D, Macclesfield, United Kingdom
| | - J. Swinton
- Computational Biology, Discovery Sciences and
| | - N. Abi-Gerges
- Safety Pharmacology, Safety Assessment United Kingdom, AstraZeneca R&D, Macclesfield, United Kingdom
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24
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Swensen AM, Niforatos W, Vortherms TA, Perner RJ, Li T, Schrimpf MR, Scott VE, Lee L, Jarvis MF, McGaraughty S. An automated electrophysiological assay for differentiating Ca(v)2.2 inhibitors based on state dependence and kinetics. Assay Drug Dev Technol 2012; 10:542-50. [PMID: 22428804 DOI: 10.1089/adt.2011.437] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Ca(V)2.2 (N-type) calcium channels are key regulators of neurotransmission. Evidence from knockout animals and localization studies suggest that Ca(V)2.2 channels play a critical role in nociceptive transmission. Additionally, ziconotide, a selective peptide inhibitor of Ca(V)2.2 channels, is clinically used to treat refractory pain. However, the use of ziconotide is limited by its low therapeutic index, which is believed, at least in part, to be a consequence of ziconotide inhibiting Ca(V)2.2 channels regardless of the channel state. Subsequent efforts have focused on the discovery of state-dependent inhibitors that preferentially bind to the inactivated state of Ca(V)2.2 channels in order to achieve an improved safety profile relative to ziconotide. Much less attention has been paid to understanding the binding kinetics of these state-dependent inhibitors. Here, we describe a novel electrophysiology-based assay on an automated patch platform designed to differentiate Ca(V)2.2 inhibitors based on their combined state dependence and kinetics. More specifically, this assay assesses inactivated state block, closed state block, and monitors the kinetics of recovery from block when channels move between states. Additionally, a use-dependent assay is described that uses a train of depolarizing pulses to drive channels to a similar level of inactivation for comparison. This use-dependent protocol also provides information on the kinetics of block development. Data are provided to show how these assays can be utilized to screen for kinetic diversity within and across chemical classes.
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Affiliation(s)
- Andrew M Swensen
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, Illinois 60064-6118, USA.
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25
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Rao AU, Shao N, Aslanian RG, Chan TY, Degrado SJ, Wang L, McKittrick B, Senior M, West RE, Williams SM, Wu RL, Hwa J, Patel B, Zheng S, Sondey C, Palani A. Discovery of a potent thiadiazole class of histamine h3 receptor antagonist for the treatment of diabetes. ACS Med Chem Lett 2012; 3:198-202. [PMID: 24900450 DOI: 10.1021/ml200250t] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 11/20/2011] [Indexed: 12/31/2022] Open
Abstract
A series of novel 2-piperidinopiperidine thiadiazoles were synthesized and evaluated as new leads of histamine H3 receptor antagonists. The 4-(5-([1,4'-bipiperidin]-1'-yl)-1,3,4-thiadiazol-2-yl)-2-(pyridin-2-yl)morpholine (5u) displayed excellent potency and ex vivo receptor occupancy. Compound 5u was also evaluated in vivo for antidiabetic efficacy in STZ diet-induced obesity type 2 diabetic mice for 2 or 12 days. Non-fasting glucose levels were significantly reduced as compared with vehicle-treated mice. In addition, 5u dose dependently blocked the increase of HbA1c after 12 days of treatment.
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Affiliation(s)
- Ashwin U. Rao
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Ning Shao
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Robert G. Aslanian
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Tin-Yau Chan
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Sylvia J. Degrado
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Li Wang
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Brian McKittrick
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Mary Senior
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Robert E. West
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Shirley M. Williams
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Ren-Long Wu
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Joyce Hwa
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Bhuneshwari Patel
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Shuqin Zheng
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Christopher Sondey
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
| | - Anandan Palani
- Department
of Medicinal Chemistry and ‡Cardiovascular/Metabolic Disease, Merck Research Laboratories, 2015 Galloping Hill Road,
Kenilworth, New Jersey 07033, United States
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26
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Synthesis and structure–activity relationship (SAR) study of 4-azabenzoxazole analogues as H3 antagonists. Bioorg Med Chem Lett 2012; 22:2075-8. [DOI: 10.1016/j.bmcl.2012.01.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 01/03/2012] [Accepted: 01/09/2012] [Indexed: 11/24/2022]
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27
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Orally bioavailable allosteric CCR8 antagonists inhibit dendritic cell, T cell and eosinophil migration. Biochem Pharmacol 2011; 83:778-87. [PMID: 22209712 DOI: 10.1016/j.bcp.2011.12.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Revised: 12/14/2011] [Accepted: 12/15/2011] [Indexed: 11/24/2022]
Abstract
The chemokine receptor CCR8 is associated with asthma. Herein, we describe that both mature and immature dendritic cells (DC) express CCR8, whereas only mature DC migrate towards CCL1. Moreover, transient LPS challenge significantly down-regulates CCR8 expression hence attenuating CCL1 chemotaxis. To inhibit CCR8 pathophysiology, we recently developed a novel series of small molecule CCR8 antagonists containing a diazaspiroundecane scaffold, which had micromolar potency. However, these first generation antagonists had high lipophilicity that endowed the compounds with poor physicochemical properties, and were thus not suitable for further development. By introducing polar bicyclic groups on the N-benzyl substituent and building in further polar interactions on the amide group we now show second generation diazospiroundecane antagonists with significantly improved overall properties. Potency is substantially improved from micromolar to nanomolar potency in CCR8 binding and inhibition of chemotaxis in human primary T cells, DC and in an eosinophil cell line. In addition to high potency, the most attractive antagonist, AZ084 showed excellent selectivity, high metabolic stability in vitro and an attractive in vivo PK profile with a long half-life in rat. Interestingly, in ligand saturation experiments and in wash-off experiments, CCL1 was shown to have two binding sites to CCR8 with K(d) at 1.2/68pM respectively, and on-off rates of 0.004 and 0.0035/0.02pMmin, respectively. The lead antagonist, AZ084, appears to act as an allosteric inhibitor with a K(i) at 0.9nM. Taken together, we herein report a novel oral allosteric CCR8 antagonist with predicted low once-daily dosing capable of potent inhibition of both human T cell and DC functions.
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Abi-Gerges N, Holkham H, Jones EMC, Pollard CE, Valentin JP, Robertson GA. hERG subunit composition determines differential drug sensitivity. Br J Pharmacol 2011; 164:419-32. [PMID: 21449979 PMCID: PMC3188906 DOI: 10.1111/j.1476-5381.2011.01378.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Revised: 03/04/2011] [Accepted: 03/07/2011] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE The majority of human ether-a-go-go-related gene (hERG) screens aiming to minimize the risk of drug-induced long QT syndrome have been conducted using heterologous systems expressing the hERG 1a subunit, although both hERG 1a and 1b subunits contribute to the K+ channels producing the repolarizing current I(Kr) . We tested a range of compounds selected for their diversity to determine whether hERG 1a and 1a/1b channels exhibit different sensitivities that may influence safety margins or contribute to a stratified risk analysis. EXPERIMENTAL APPROACH We used the IonWorks™ plate-based electrophysiology device to compare sensitivity of hERG 1a and 1a/1b channels stably expressed in HEK293 cells to 50 compounds previously shown to target hERG channels. Potency was determined as IC₅₀ values (µM) obtained from non-cumulative, eight-point concentration-effect curves of normalized data, fitted to the Hill equation. To minimize possible sources of variability, compound potency was assessed using test plates arranged in alternating columns of cells expressing hERG 1a and 1a/1b. KEY RESULTS Although the potency of most compounds was similar for the two targets, some surprising differences were observed. Fluoxetine (Prozac) was more potent at blocking hERG 1a/1b than 1a channels, yielding a corresponding reduction in the safety margin. In contrast, E-4031 was a more potent blocker of hERG 1a compared with 1a/1b channels, as previously reported, as was dofetilide, another high-affinity blocker. CONCLUSIONS AND IMPLICATIONS The current assays may underestimate the risk of some drugs to cause torsades de pointes arrhythmia, and overestimate the risk of others.
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Affiliation(s)
- N Abi-Gerges
- Safety Pharmacology, Safety Assessment UK, AstraZeneca R&D Alderley Park, Macclesfield, UK.
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Xia Y, Chackalamannil S, Greenlee WJ, Jayne C, Neustadt B, Stamford A, Vaccaro H, Xu X(L, Baker H, O’Neill K, Woods M, Hawes B, Kowalski T. Discovery of a nortropanol derivative as a potent and orally active GPR119 agonist for type 2 diabetes. Bioorg Med Chem Lett 2011; 21:3290-6. [DOI: 10.1016/j.bmcl.2011.04.035] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 04/04/2011] [Accepted: 04/07/2011] [Indexed: 12/01/2022]
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30
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Golden AP, Li N, Chen Q, Lee T, Nevill T, Cao X, Johnson J, Erdemli G, Ionescu-Zanetti C, Urban L, Holmqvist M. IonFlux: a microfluidic patch clamp system evaluated with human Ether-à-go-go related gene channel physiology and pharmacology. Assay Drug Dev Technol 2011; 9:608-19. [PMID: 21561375 DOI: 10.1089/adt.2010.0362] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Ion channel assays are essential in drug discovery, not only for identifying promising new clinical compounds, but also for minimizing the likelihood of potential side effects. Both applications demand optimized throughput, cost, and predictive accuracy of measured membrane current changes evoked or modulated by drug candidates. Several competing electrophysiological technologies are available to address this demand, but important gaps remain. We describe the industrial application of a novel microfluidic-based technology that combines compounds, cells, and buffers on a single, standard well plate. Cell trapping, whole cell, and compound perfusion are accomplished in interconnecting microfluidic channels that are coupled to pneumatic valves, which emancipate the system from robotics, fluidic tubing, and associated maintenance. IonFlux™ is a state-of-the-art, compact system with temperature control and continuous voltage clamp for potential application in screening for voltage- and ligand-gated ion channel modulators. Here, ensemble recordings of the IonFlux system were validated with the human Ether-à-go-go related gene (hERG) channel (stably expressed in a Chinese hamster ovary cell line), which has established biophysical and pharmacological characteristics in other automated planar patch systems. We characterized the temperature dependence of channel activation and its reversal potential. Concentration response characteristics of known hERG blockers and control compounds obtained with the IonFlux system correlated with literature and internal data obtained on this cell line with the QPatch HT system. Based on the biophysical and pharmacological data, we conclude that the IonFlux system offers a novel, versatile, automated profiling, and screening system for ion channel targets with the benefit of temperature control.
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Affiliation(s)
- Andrew P Golden
- Preclinical Safety Profiling, Center for Proteomic Chemistry, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts 02139, USA
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31
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Cao X, Lee YT, Holmqvist M, Lin Y, Ni Y, Mikhailov D, Zhang H, Hogan C, Zhou L, Lu Q, Digan ME, Urban L, Erdemli G. Cardiac ion channel safety profiling on the IonWorks Quattro automated patch clamp system. Assay Drug Dev Technol 2010; 8:766-80. [PMID: 21133679 DOI: 10.1089/adt.2010.0333] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The normal electrophysiologic behavior of the heart is determined by the integrated activity of specific cardiac ionic currents. Mutations in genes encoding the molecular components of individual cardiac ion currents have been shown to result in multiple cardiac arrhythmia syndromes. Presently, 12 genes associated with inherited long QT syndrome (LQTS) have been identified, and the most common mutations are in the hKCNQ1 (LQT1, Jervell and Lange-Nielson syndrome), hKCNH2 (LQT2), and hSCN5A (LQT3, Brugada syndrome) genes. Several drugs have been withdrawn from the market or received black box labeling due to clinical cases of QT interval prolongation, ventricular arrhythmias, and sudden death. Other drugs have been denied regulatory approval owing to their potential for QT interval prolongation. Further, off-target activity of drugs on cardiac ion channels has been shown to be associated with increased mortality in patients with underlying cardiovascular diseases. Since clinical arrhythmia risk is a major cause for compound termination, preclinical profiling for off-target cardiac ion channel interactions early in the drug discovery process has become common practice in the pharmaceutical industry. In the present study, we report assay development for three cardiac ion channels (hKCNQ1/minK, hCa(v)1.2, and hNa(v)1.5) on the IonWorks Quattro™ system. We demonstrate that these assays can be used as reliable pharmacological profiling tools for cardiac ion channel inhibition to assess compounds for cardiac liability during drug discovery.
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Affiliation(s)
- Xueying Cao
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Sciences Inc., Cambridge, Massachusetts 02139, USA
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32
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Bridal TR, Margulis M, Wang X, Donio M, Sorota S. Comparison of Human Ether-à-go-go Related Gene Screening Assays Based on IonWorks Quattro and Thallium Flux. Assay Drug Dev Technol 2010; 8:755-65. [DOI: 10.1089/adt.2010.0267] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Terry R. Bridal
- Department of Neurosciences, Merck Research Labs, Kenilworth, New Jersey
| | - Michael Margulis
- Department of Neurosciences, Merck Research Labs, Kenilworth, New Jersey
| | - Xin Wang
- Department of Neurosciences, Merck Research Labs, Kenilworth, New Jersey
| | - Michael Donio
- Department of Neurosciences, Merck Research Labs, Kenilworth, New Jersey
| | - Steve Sorota
- Department of Neurosciences, Merck Research Labs, Kenilworth, New Jersey
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33
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Schmalhofer WA, Swensen AM, Thomas BS, Felix JP, Haedo RJ, Solly K, Kiss L, Kaczorowski GJ, Garcia ML. A Pharmacologically Validated, High-Capacity, Functional Thallium Flux Assay for the Human Ether-à-go-go Related Gene Potassium Channel. Assay Drug Dev Technol 2010; 8:714-26. [DOI: 10.1089/adt.2010.0351] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
| | - Andrew M. Swensen
- Department of Ion Channels, Merck Research Laboratories, Rahway, New Jersey
| | - Brande S. Thomas
- Department of Ion Channels, Merck Research Laboratories, Rahway, New Jersey
| | - John P. Felix
- Department of Ion Channels, Merck Research Laboratories, Rahway, New Jersey
| | - Rodolfo J. Haedo
- Department of Ion Channels, Merck Research Laboratories, Rahway, New Jersey
| | - Kelli Solly
- Department of Automated Biotechnology, Merck Research Laboratories, North Wales, Pennsylvania
| | - Laszlo Kiss
- Department of Automated Biotechnology, Merck Research Laboratories, North Wales, Pennsylvania
| | | | - Maria L. Garcia
- Department of Ion Channels, Merck Research Laboratories, Rahway, New Jersey
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34
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Trivedi S, Liu J, Liu R, Bostwick R. Advances in functional assays for high-throughput screening of ion channels targets. Expert Opin Drug Discov 2010; 5:995-1006. [DOI: 10.1517/17460441.2010.513377] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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35
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Discovery of imidazo[1,2-a]pyrazine-based Aurora kinase inhibitors. Bioorg Med Chem Lett 2010; 20:5170-4. [PMID: 20674350 DOI: 10.1016/j.bmcl.2010.07.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Revised: 07/01/2010] [Accepted: 07/02/2010] [Indexed: 11/20/2022]
Abstract
The synthesis and structure-activity relationships (SAR) of novel, potent imidazo[1,2-a]pyrazine-based Aurora kinase inhibitors are described. The X-ray crystal structure of imidazo[1,2-a]pyrazine Aurora inhibitor 1j is disclosed. Compound 10i was identified as lead compound with a promising overall profile.
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36
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Abstract
For every movement, heartbeat and thought, ion channels need to open and close. It is therefore not surprising that their malfunctioning leads to serious diseases. Currently, only approximately 10% of drugs, with a market value in excess of US$10 billion, act on ion channels. The systematic exploitation of this target class has started, enabled by novel assay technologies and fundamental advances of the structural and mechanistic understanding of channel function. The latter, which was rewarded with the Nobel Prize in 2003, has opened up an avenue for rational drug design. In this review we provide an overview of the current repertoire of screening technologies that has evolved to drive ion channel-targeted drug discovery towards new medicines of the future.
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37
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Berlin M, Lee YJ, Boyce CW, Wang Y, Aslanian R, McCormick KD, Sorota S, Williams SM, West RE, Korfmacher W. Reduction of hERG inhibitory activity in the 4-piperidinyl urea series of H3 antagonists. Bioorg Med Chem Lett 2010; 20:2359-64. [PMID: 20188550 DOI: 10.1016/j.bmcl.2010.01.121] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 01/21/2010] [Accepted: 01/21/2010] [Indexed: 11/16/2022]
Abstract
Structural features of the substituted 4-piperidinyl urea analogs 1, responsible for the H3 antagonist activity, have been identified. Structure-activity relationship of the H3 receptor affinity, hERG ion channel inhibitory activity and their separation is described. Preliminary pharmacokinetic evaluation of the compounds of the series is addressed.
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Affiliation(s)
- Michael Berlin
- Chemical Research, Cardiovascular/Metabolic Diseases and CNS Discovery, and Drug Metabolism and Pharmacokinetics, Merck Research Laboratories, Kenilworth, NJ 07033, USA.
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38
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Mikhailov D, Traebert M, Lu Q, Whitebread S, Egan W. Should Cardiosafety be Ruled by hERG Inhibition? Early Testing Scenarios and Integrated Risk Assessment. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/9783527627448.ch16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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39
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Rao AU, Palani A, Chen X, Huang Y, Aslanian RG, West RE, Williams SM, Wu RL, Hwa J, Sondey C, Lachowicz J. Synthesis and structure-activity relationships of 2-(1,4'-bipiperidin-1'-yl)thiazolopyridine as H3 receptor antagonists. Bioorg Med Chem Lett 2009; 19:6176-80. [PMID: 19773164 DOI: 10.1016/j.bmcl.2009.09.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Revised: 08/31/2009] [Accepted: 09/02/2009] [Indexed: 11/28/2022]
Abstract
A series of 2-(1,4'-bipiperidine-1'-yl)thiazolopyridines was synthesized and evaluated as a new lead of non-imidazole histamine H(3) receptor antagonists. Introduction of diversity at the 6-position of the pyridine ring was designed to enhance in vitro potency and decrease hERG activity. The structure-activity relationships for these new thiazolopyridine antagonists are discussed.
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Affiliation(s)
- Ashwin U Rao
- Schering-Plough Research Institute, 2015 Galloping Hill Road, K-15-1-1800, Kenilworth, NJ 07033, USA.
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40
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Aslanian R, Piwinski JJ, Zhu X, Priestley T, Sorota S, Du XY, Zhang XS, McLeod RL, West RE, Williams SM, Hey JA. Structural determinants for histamine H1 affinity, hERG affinity and QTc prolongation in a series of terfenadine analogs. Bioorg Med Chem Lett 2009; 19:5043-7. [DOI: 10.1016/j.bmcl.2009.07.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 07/06/2009] [Accepted: 07/08/2009] [Indexed: 01/08/2023]
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41
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Hansen K, Rathke F, Schroeter T, Rast G, Fox T, Kriegl JM, Mika S. Bias-Correction of Regression Models: A Case Study on hERG Inhibition. J Chem Inf Model 2009; 49:1486-96. [DOI: 10.1021/ci9000794] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Katja Hansen
- University of Technology, Berlin, Germany, Departments of Drug Discovery Support and Lead Discovery, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach a.d. Riss, Germany, and idalab GmbH, Berlin, Germany
| | - Fabian Rathke
- University of Technology, Berlin, Germany, Departments of Drug Discovery Support and Lead Discovery, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach a.d. Riss, Germany, and idalab GmbH, Berlin, Germany
| | - Timon Schroeter
- University of Technology, Berlin, Germany, Departments of Drug Discovery Support and Lead Discovery, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach a.d. Riss, Germany, and idalab GmbH, Berlin, Germany
| | - Georg Rast
- University of Technology, Berlin, Germany, Departments of Drug Discovery Support and Lead Discovery, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach a.d. Riss, Germany, and idalab GmbH, Berlin, Germany
| | - Thomas Fox
- University of Technology, Berlin, Germany, Departments of Drug Discovery Support and Lead Discovery, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach a.d. Riss, Germany, and idalab GmbH, Berlin, Germany
| | - Jan M. Kriegl
- University of Technology, Berlin, Germany, Departments of Drug Discovery Support and Lead Discovery, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach a.d. Riss, Germany, and idalab GmbH, Berlin, Germany
| | - Sebastian Mika
- University of Technology, Berlin, Germany, Departments of Drug Discovery Support and Lead Discovery, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach a.d. Riss, Germany, and idalab GmbH, Berlin, Germany
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42
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Pugsley MK, Authier S, Curtis MJ. Principles of safety pharmacology. Br J Pharmacol 2008; 154:1382-99. [PMID: 18604233 PMCID: PMC2492105 DOI: 10.1038/bjp.2008.280] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Revised: 06/09/2008] [Accepted: 06/12/2008] [Indexed: 11/09/2022] Open
Abstract
Safety Pharmacology is a rapidly developing discipline that uses the basic principles of pharmacology in a regulatory-driven process to generate data to inform risk/benefit assessment. The aim of Safety Pharmacology is to characterize the pharmacodynamic/pharmacokinetic (PK/PD) relationship of a drug's adverse effects using continuously evolving methodology. Unlike toxicology, Safety Pharmacology includes within its remit a regulatory requirement to predict the risk of rare lethal events. This gives Safety Pharmacology its unique character. The key issues for Safety Pharmacology are detection of an adverse effect liability, projection of the data into safety margin calculation and finally clinical safety monitoring. This article sets out to explain the drivers for Safety Pharmacology so that the wider pharmacology community is better placed to understand the discipline. It concludes with a summary of principles that may help inform future resolution of unmet needs (especially establishing model validation for accurate risk assessment). Subsequent articles in this issue of the journal address specific aspects of Safety Pharmacology to explore the issues of model choice, the burden of proof and to highlight areas of intensive activity (such as testing for drug-induced rare event liability, and the challenge of testing the safety of so-called biologics (antibodies, gene therapy and so on.).
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Affiliation(s)
- M K Pugsley
- Department of Toxicology & Pathology, Global Preclinical Development, Johnson & Johnson Pharmaceutical Research & Development Raritan, NJ, USA
| | - S Authier
- LAB Research Inc., 445 Armand Frappier, Laval Quebec, Canada
| | - M J Curtis
- Cardiovascular Division St Thomas' Hospital, King's College London, London, UK
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43
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Hancox JC, McPate MJ, El Harchi A, Zhang YH. The hERG potassium channel and hERG screening for drug-induced torsades de pointes. Pharmacol Ther 2008; 119:118-32. [PMID: 18616963 DOI: 10.1016/j.pharmthera.2008.05.009] [Citation(s) in RCA: 217] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Accepted: 05/27/2008] [Indexed: 01/08/2023]
Abstract
Drug-induced torsades de pointes (TdP) arrhythmia is a major safety concern in the process of drug design and development. The incidence of TdP tends to be low, so early pre-clinical screens rely on surrogate markers of TdP to highlight potential problems with new drugs. hERG (human ether-à-go-go-related gene, alternative nomenclature KCNH2) is responsible for channels mediating the 'rapid' delayed rectifier K+ current (IKr) which plays an important role in ventricular repolarization. Pharmacological inhibition of native IKr and of recombinant hERG channels is a shared feature of diverse drugs associated with TdP. In vitro hERG assays therefore form a key element of an integrated assessment of TdP liability, with patch-clamp electrophysiology offering a 'gold standard'. However, whilst clearly necessary, hERG assays cannot be assumed automatically to provide sufficient information, when considered in isolation, to differentiate 'safe' from 'dangerous' drugs. Other relevant factors include therapeutic plasma concentration, drug metabolism and active metabolites, severity of target condition and drug effects on other cardiac ion channels that may mitigate or exacerbate effects of hERG blockade. Increased understanding of the nature of drug-hERG channel interactions may ultimately help eliminate potential hERG blockade early in the design and development process. Currently, for promising drug candidates integration of data from hERG assays with information from other pre-clinical safety screens remains essential.
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Affiliation(s)
- Jules C Hancox
- Department of Physiology and Pharmacology, Cardiovascular Research Laboratories, Bristol Heart Institute, School of Medical Sciences, The University of Bristol, University Walk, Bristol, BS8 1TD, United Kingdom.
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44
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Pollard CE, Valentin JP, Hammond TG. Strategies to reduce the risk of drug-induced QT interval prolongation: a pharmaceutical company perspective. Br J Pharmacol 2008; 154:1538-43. [PMID: 18500356 DOI: 10.1038/bjp.2008.203] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Drug-induced prolongation of the QT interval is having a significant impact on the ability of the pharmaceutical industry to develop new drugs. The development implications for a compound causing a significant effect in the 'Thorough QT/QTc Study' -- as defined in the clinical regulatory guidance (ICH E14) -- are substantial. In view of this, and the fact that QT interval prolongation is linked to direct inhibition of the hERG channel, in the early stages of drug discovery the focus is on testing for and screening out hERG activity. This has led to understanding of how to produce low potency hERG blockers whilst retaining desirable properties. Despite this, a number of factors mean that when an integrated risk assessment is generated towards the end of the discovery phase (by conducting at least an in vivo QT assessment) a QT interval prolongation risk is still often apparent; inhibition of hERG channel trafficking and partitioning into cardiac tissue are just two confounding factors. However, emerging information suggests that hERG safety margins have high predictive value and that when hERG and in vivo non-clinical data are combined, their predictive value to man, whilst not perfect, is >80%. Although understanding the anomalies is important and is being addressed, of greater importance is developing a better understanding of TdP, with the aim of being able to predict TdP rather than using an imperfect surrogate marker (QT interval prolongation). Without an understanding of how to predict TdP risk, high-benefit drugs for serious indications may never be marketed.
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Affiliation(s)
- C E Pollard
- AstraZeneca R&D Alderley Park, Safety Assessment UK, Macclesfield, Cheshire, UK.
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45
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Dunlop J, Bowlby M, Peri R, Vasilyev D, Arias R. High-throughput electrophysiology: an emerging paradigm for ion-channel screening and physiology. Nat Rev Drug Discov 2008; 7:358-68. [PMID: 18356919 DOI: 10.1038/nrd2552] [Citation(s) in RCA: 351] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Ion channels represent highly attractive targets for drug discovery and are implicated in a diverse range of disorders, in particular in the central nervous and cardiovascular systems. Moreover, assessment of cardiac ion-channel activity of new chemical entities is now an integral component of drug discovery programmes to assess potential for cardiovascular side effects. Despite their attractiveness as drug discovery targets ion channels remain an under-exploited target class, which is in large part due to the labour-intensive and low-throughput nature of patch-clamp electrophysiology. This Review provides an update on the current state-of-the-art for the various automated electrophysiology platforms that are now available and critically evaluates their impact in terms of ion-channel screening, lead optimization and the assessment of cardiac ion-channel safety liability.
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Affiliation(s)
- John Dunlop
- Neuroscience Discovery Research, Wyeth Research, CN-8000, Princeton, New Jersey 08543, USA.
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46
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Jow F, Shen R, Chanda P, Tseng E, Zhang H, Kennedy J, Dunlop J, Bowlby MR. Validation of a medium-throughput electrophysiological assay for KCNQ2/3 channel enhancers using IonWorks HT. ACTA ACUST UNITED AC 2008; 12:1059-67. [PMID: 18087070 DOI: 10.1177/1087057107307448] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Enhancers of KCNQ channels are known to be effective in chronic pain models. To discover novel enhancers of KCNQ channels, the authors developed a medium-throughput electrophysiological assay by using the IonWorks platform. Screening of 20 CHO-K1 clones stably expressing KCNQ2/3 was performed on the IonWorks HT until the best clone (judged from seal rate, current level, and stability) was obtained. The KCNQ2/3 current amplitude in the cells was found to increase from 60 +/- 15 pA to 473 +/- 80 pA (at -10 mV), and the expression rate was increased by 56% when the cells were incubated at 27 degrees C overnight. The clone used for compound screening had a seal rate of greater than 90% and an overall success rate of greater than 70%. The voltage step protocol (hold cells at -80 mV and depolarize to -10 mV for 1 s) was designed to provide moderate current but still allow for pharmacological current enhancement. EC(50)s were generated from 8-point concentration-response curves with a control compound on each plate using compounds that were also tested with conventional patch clamp. The authors found that there was a very good correlation (R(2) > 0.9) between the 2 assays, thus demonstrating the highly predictive nature of the IonWorks assay.
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Affiliation(s)
- Flora Jow
- Discovery Neuroscience, Wyeth Research, Princeton, New Jersey 08543-8000, USA
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47
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Lee YT, Vasilyev DV, Shan QJ, Dunlop J, Mayer S, Bowlby MR. Novel pharmacological activity of loperamide and CP-339,818 on human HCN channels characterized with an automated electrophysiology assay. Eur J Pharmacol 2007; 581:97-104. [PMID: 18162181 DOI: 10.1016/j.ejphar.2007.11.058] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2007] [Revised: 11/08/2007] [Accepted: 11/21/2007] [Indexed: 11/17/2022]
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels underlie the pacemaker currents in neurons (I(h)) and cardiac (I(f)) cells. As such, the identification and characterization of novel blockers of HCN channels is important to enable the dissection of their function in vivo. Using a new IonWorks HT electrophysiology assay with human HCN1 and HCN4 expressed stably in cell lines, four HCN channel blockers are characterized. Two blockers known for their activity at opioid/Ca(2+) channels and K(+) channels, loperamide and CP-339,818 (respectively), are described to block HCN1 more potently than HCN4. The known HCN blocker ZD7288 was also found to be more selective for HCN1 over HCN4, while the HCN blocker DK-AH269 was equipotent on HCN4 and HCN1. Partial replacement of the intracellular Cl(-) with gluconate reduced the potency on both channels, but to varying degrees. For both HCN1 and HCN4, ZD7288 was most sensitive in lower Cl(-) solutions, while the potency of loperamide was not affected by the differing solutions. The block of HCN1 for all compounds was voltage-dependent, being relieved at more negative potentials. The voltage-dependent, Cl(-) dependent, HCN1 preferring compounds described here elaborate on the current known pharmacology of HCN channels and may help provide novel tools and chemical starting points for the investigation of HCN channel function in natively expressing systems.
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Affiliation(s)
- Yan T Lee
- Discovery Neuroscience, Wyeth Research, CN 8000, Princeton, NJ 08543-8000, United States
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Houck KA, Kavlock RJ. Understanding mechanisms of toxicity: insights from drug discovery research. Toxicol Appl Pharmacol 2007; 227:163-78. [PMID: 18063003 DOI: 10.1016/j.taap.2007.10.022] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Revised: 09/28/2007] [Accepted: 10/11/2007] [Indexed: 12/18/2022]
Abstract
Toxicology continues to rely heavily on use of animal testing for prediction of potential for toxicity in humans. Where mechanisms of toxicity have been elucidated, for example endocrine disruption by xenoestrogens binding to the estrogen receptor, in vitro assays have been developed as surrogate assays for toxicity prediction. This mechanistic information can be combined with other data such as exposure levels to inform a risk assessment for the chemical. However, there remains a paucity of such mechanistic assays due at least in part to lack of methods to determine specific mechanisms of toxicity for many toxicants. A means to address this deficiency lies in utilization of a vast repertoire of tools developed by the drug discovery industry for interrogating the bioactivity of chemicals. This review describes the application of high-throughput screening assays as experimental tools for profiling chemicals for potential for toxicity and understanding underlying mechanisms. The accessibility of broad panels of assays covering an array of protein families permits evaluation of chemicals for their ability to directly modulate many potential targets of toxicity. In addition, advances in cell-based screening have yielded tools capable of reporting the effects of chemicals on numerous critical cell signaling pathways and cell health parameters. Novel, more complex cellular systems are being used to model mammalian tissues and the consequences of compound treatment. Finally, high-throughput technology is being applied to model organism screens to understand mechanisms of toxicity. However, a number of formidable challenges to these methods remain to be overcome before they are widely applicable. Integration of successful approaches will contribute towards building a systems approach to toxicology that will provide mechanistic understanding of the effects of chemicals on biological systems and aid in rationale risk assessments.
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Affiliation(s)
- Keith A Houck
- National Center for Computational Toxicology, Office Research and Development, United Stated Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
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Su J, Tang H, McKittrick BA, Gu H, Guo T, Qian G, Burnett DA, Clader JW, Greenlee WJ, Hawes BE, O'neill K, Spar B, Weig B, Kowalski T, Sorota S. Synthesis of novel bicyclo[4.1.0]heptane and bicyclo[3.1.0]hexane derivatives as melanin-concentrating hormone receptor R1 antagonists. Bioorg Med Chem Lett 2007; 17:4845-50. [PMID: 17604169 DOI: 10.1016/j.bmcl.2007.06.048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2007] [Revised: 06/11/2007] [Accepted: 06/13/2007] [Indexed: 10/23/2022]
Abstract
To address the hERG liability of MCHR1 antagonists such as 1 and 2, new analogs such as 4 and 5 that incorporated a polar heteroaryl group were designed and synthesized. Biological evaluation confirmed that these new analogs retained MCH R1 activity with greatly attenuated hERG liabilities as indicated in the Rb efflux assay.
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Affiliation(s)
- Jing Su
- Department of Chemical Research, Schering-Plough Research Institute K15 2545, Kenilworth, NJ 07033, USA.
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Gill S, Gill R, Wicks D, Liang D. A cell-based Rb(+)-flux assay of the Kv1.3 potassium channel. Assay Drug Dev Technol 2007; 5:373-80. [PMID: 17638537 DOI: 10.1089/adt.2006.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The Kv1.3 channels expressed by human T lymphocytes are emerging as important therapeutic targets. Peptides like agitoxin and margatoxin in scorpion venom and some non-peptide small molecules are known to inhibit this channel. Since such blockers cannot be used as drugs, pharma has a need to discover effective blockers. The major limiting factor for such development has been the lack of a reliable high-throughput screening (HTS) technology. A cell-based HTS assay for this target was developed in 96-well format to facilitate screening of many candidates. The assay incorporates rubidium ion as a tracer for potassium ion, which can be analyzed by the atomic absorption spectroscopy. The assay provided a Z' factor of 0.813 with more than a 4.5-fold window of detection. The two known blockers agitoxin and margatoxin gave a 50% inhibitory concentration (IC(50)) of 1.52 and 2 nM, respectively. These values are about five- and 2.8-fold higher than their IC(50) values obtained from patch clamp. Some non-peptide compounds like tamoxifen, nifedipine, and fluoxetine also inhibited the efflux through these channels, whereas astemizole and pimozide (potent human ether-a-go-go-related gene blockers) did not block Kv1.3 activity.
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